Nine members of NASA’s Rock Powered Life (RPL) Astrobiology Institute, representing 4 RPL labs from across the country, joined together in a field campaign to sample deep subsurface hyperalkaline fluids in the Samail Ophiolite, Sultanate of Oman. Researcher Eric Ellison and graduate students Daniel Nothaft and Kaitlin Rempfert along with RPL Principle Investigator (PI) Alexis Templeton (CU Boulder), post-doc Lauren Seyler from Co-I Matt Schrenk’s group (Michigan State), graduate student Emily Kraus and Co-I John Spear (Colorado School of Mines), and graduate student Laura Bueter and Co-I Eric Boyd (Montana State) converged to conduct a nine-day field campaign in the peridotite mountain catchments near Ibra. The goal was to collect deep alkaline fluid samples to generate new insights into how the process of serpentinization shapes the distribution and activity of life in this early earth and astrobiology analog environment. In this first phase of a three-phase approach, water samples and associated microbiology and dissolved gases were obtained from a number of existing drill holes, ranging in depth from 50 – 400m. Members of the Templeton group focused on collection of samples for characterization hydrocarbons and microbial lipids, and to deploy in-situ mineral reactivity experiments. The Spear group collected samples for single cell and metagenomics analyses of rock hosted microbial communities. Seyler employed tangential flow filtration to concentrate samples for metabolite analyses and also collected materials for targeted single cell genomics. The Boyd group processed samples for use in determining the abundance and activities of microbial populations involved in several carbon transformation processes across strong gradients in pH, H2, CO2 and CO. The field team also collected samples for two other RPL labs, including dissolved methane for isotopologue analysis by graduate student Jeemin Rhim (Ono lab) and sulfate-rich fluids for sulfate reduction rate assays by NPP fellow Clemens Glombita (Hoehler lab).
The RPL team in Oman joins forces with members of the Oman Drilling Project. The team from left to right: Louise Koornneef OmanDP, OmanDP geologist, Jude Coggon OmanDP, OmanDP geologist, Alexis Templeton, OmanDP geologist, Laura Beuter, Eric Boyd, Lauren Seyler, Eric Ellison, Kaitlin Rempfert, Dan Nothaft, Peter Kelemen, Emily Kraus, John Spear, Nehal OmanDP driller.
The nine days in the field provided abundant opportunities for the students, research scientists, postdocs, and Co-Is to discuss new ways to integrate the complementary data streams generated from the work, plan follow-on experimentation, better understand how to perform science in the desert environment of Oman, and develop a deeper sense of comradery among members of the group. Importantly, the group also was provided access to on-going drilling operations associated with the Oman Drilling Program (OmanDP), and opportunities were available to discuss the logistics of future biological sampling of drill cores by RPL members with OmanDP PIs and RPL collaborators Peter Kelemen and Juerg Matter and on-site project coordinator Jude Coggon. RPL member labs were provided with a subsample of gabbro core to be used in preliminary site characterization of the mineralogy, microbial community diversity, and community function. Members of the RPL field team are excited to begin planning for Phase 2 of Oman astrobiological research, which will use freshly obtained drill core samples to develop a new understanding of life activity and preservation in cores from serpentinites sampled from deep beneath Earth’s surface as we approach the suspected thermodynamic limits for life. It is anticipated that the RPL membership working in Oman to characterize serpentinite drill cores and fluids will continue to grow in Phase 2, with return visits in 2018 by the 2017 field team, as well as greater participation by the Shock, Tominaga, Schrenk, Hoehler, Cardace, and Ono lab members that have applied to participate in OmanDP. Phase 3 will involve the integration of microbiological studies into plans to pack-off drill holes and more directly target the hydrogeochemical and life processes occurring within discrete reaction zones within the actively serpentinizing system.